Math lesson plan · 8th grade (Year 9 in England) · 45 minutes
Compare and order numbers in scientific notation
Number sense
CCSS 8.EE.A.3England: KS3 NumberEngland: GCSE Foundation Number
Objective and success criteria
Students will: Compare and order numbers in scientific notation.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Write numbers in scientific notation (standard form)
Leads to: the next skill in this area.
Materials: Place value chart, Base-ten blocks or a number line, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Write numbers in scientific notation (standard form)). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Write 9 700 000 in scientific notation (like 4.5 × 10^6). → 9.7 × 10⁶Prompt: The first number must be at least 1 and less than 10.
- Write 0.0000038 in scientific notation. → 3.8 × 10⁻⁶Prompt: Move the decimal point to just after the first non-zero digit.
- Luis writes 8 000 000 as 80 × 10⁵. Why is that not scientific notation? (The value is wrong / The power of 10 must be negative / You cannot use decimals / 80 is not between 1 and 10) → 80 is not between 1 and 10Prompt: Is the value correct? Check by multiplying out.
Hook · 5 min
- Show a number in the news or a price tag and ask what each digit is worth.
- Share the objective: Compare and order numbers in scientific notation. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Which is larger: 8.9 × 10⁵ or 7.3 × 10⁶?
- Step 1: 7.3 × 10⁶ is larger.
- Answer: 7.3 × 10⁶
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Which is larger: 5.2 × 10⁶ or 3.5 × 10⁷? (5.2 × 10⁶ / 3.5 × 10⁷) → 3.5 × 10⁷Prompt: Compare the powers of 10 first.
- Which is larger: 2.5 × 10⁴ or 4 × 10⁵? (2.5 × 10⁴ / 4 × 10⁵) → 4 × 10⁵Prompt: Compare the powers of 10 first.
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- Which is larger: 2.5 × 10⁵ or 6.8 × 10⁶? (2.5 × 10⁵ / 6.8 × 10⁶) → 6.8 × 10⁶Prompt: Compare the powers of 10 first.
- Which is larger: 9.6 × 10⁴ or 1.6 × 10⁵? (9.6 × 10⁴ / 1.6 × 10⁵) → 1.6 × 10⁵Prompt: Compare the powers of 10 first.
Watch out for
- Reading 1,045 as one thousand four hundred five: point to each place and say its value.
- Thinking a longer number is always bigger, even with decimals (0.45 vs 0.5).
Support and stretch
Support
- Review first: Write numbers in scientific notation (standard form).
- Use concrete materials: place value chart.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-8.
Free lesson plan from eurekami.com/lesson-plan-builder